I first tried by calling 2 plumbers but thing are so busy they don’t want to do such a small and dirty job but my project must move on.
I want to cut out a section to install a pvc tee in 2 places (probabally better to replace the big section then 2 little sections. I see it was done before up higher so I know it can be done (big rubber sleave over the cuts between the cast iron and the PVC).
So
1 - How do I cut it?
2 - What are the chances my cutting will cause a crack in the wrong direction?
3 - Should I do something to support the weight of the section that will be suspended until the sleave inserted?
THis is for a main drain stack where the top is throught the roof, then bathroom fixtures tie in, then kitchen, then into the slab where it has to turn towards the trap.
Here’s a site describing various cutting methods. The snap cutter (with the chain) is the one I’ve heard of before. It requires special tools and doesn’t look like an easy job. I would absolutely support both ends of the cut, this is very heavy pipe. I don’t have any real experience, so I don’t know how easy it is to screw up and damage the pipe.
You can buy a saddle. You use a hole saw and a big electric drill to cut a hole in the right position(harder than it sounds) and clamp on a saddle and a gasket. The saddle has either a tee or a wye junction, and is held in place with a couple of beefy clamps. It beats cutting the pipe out .
If you have to cut the pipe, the snap cutter works really well, but if it’s old cast, as in 60-70 years old, it can be so brittle it shatters. A big sawzall works well for this, then you insert the new wye and clamp it in place with rubber boots and clamps.
Good luck!
b.